The present invention is concerned with an improved modular assembly, consisting of a rack or support frame with two side walls, two front transverse support members and two rear transverse support members and at least one guide unit having a pair of guide rails latchably attachable to the transverse support members as well as a module support with connectors for electrical connection with corresponding connectors provided on the rear transverse support members.
From German Published Patent Specification No. 2,007,303, published Sept. 10, 1970, there is known a modular assembly with a rack of the above type. In such modular assembly there is provided a multiplicity of spaced apart threaded holes on the rear support members for the purpose of fastening spaced-apart connectors. The connectors, which are intended for electrical connection with insertable module supports are attached to the support members with screws, which serve simultaneously for the attachment of the rear ends of the lower and upper guide rails to the support members. At their front ends the guide rails are provided with noses, which snap into corresponding holes in additional upper and lower metal strips. Provision of the threaded holes in the support members is expensive having regard to the close tolerances required and to the substantial labor costs for the assembly and attachment of the connectors.
If, for example, a connector is to be replaced, it is necessary in the known rack to loosen and remove the corresponding screws. It can also happen quite easily with this modular assembly that during operational use a screw could work itself loose because of constant vibration and fall between the other module supports and cause a short-circuit or become lost.